It has some patent issues, so it might not be in your Linux distribution standard repository.

I am using that on my Intel system, and it least I am able to play Lord of the Rings online (via Wine) succesfully with it.

If you still have problems with it, try to install & run driconf, and enable option "Enable S3TC texture compression..." from page Image Quality. You may need to log off and log on again to apply the change.